Raman spectroscopic study of superconducting Bi1.6Pb0.4sR2Ca2Cu3Oy

The polycrystalline samples of Bi 1.6 Pb 0.4 Sr 2 Cu 3 O y were prepared by the melt-quenching method, and examined by Raman spectroscopy. In these samples, the c-axis of each plate-like microcrystal was parallel to the surface of the samples. The Raman spectra of the two surfaces of a sample were found to differ each other, especially in the intensity of the 660 cm -1 phonon line